@charset "utf-8";

$red:red;
$color:yellow;
$font-size:12px;

@mixin bgg($wid,$hei,$back){
    width: $wid;
    height:$hei;
    background:$back;
}

body{
    background:black;
}

.baba{
    @include bgg(500px,500px,black);
    >div{
       @include bgg(300px,300px,$color);
        >div{
           @include bgg(100px,100px,$red);
        }
    }
}



.a{
    li{
        @include bgg(100px,100px,yellowgreen);
    }
    li:nth-child(2){
        width: 100px;
        height: 100px;
        background: red;
    }
    li:nth-child(2)~li{
        @include bgg(100px,100px,yellowgreen);
    }
}
